WordWalk Puzzle Solving Strategies (Part 1)

It is important for two reasons (but perhaps a little tedious) to find all of the subwords before guessing the rootword.   The first reason is that (as of the current implementation) you get an extra 10 points for each subword correctly guessed.  

The other reason is that you can now take advantage of the arrows that have not yet been used by any of the subwords thus far and hence must be arrows belonging to the rootword.  Two nodes connected by an arrow indicates that the digram (two consecutive letters in a word) must be present somewhere in the rootword.  This can give you a major clue as to what the rootword is.

Consider the following German WordWalk Puzzle in which all of the subwords have been found but the rootword still needs to be guessed:

 

You'll notice that there is only one thin black arrow that has not yet turned green. Otherwise, all the nodes and edges (aka arrows) have been traversed at least once.  This tells us that the digram "EN" must be part of the rootword.  It doesn't tell you where in the rootword that digram occurs, but it is a constraint that narrows the search for the rootword.   We also given (when we started) that the rootword must begin with "W".

Some examples of German words that include this digram are "WENIG", "WENIGES", and perhaps some more, but I can't think of any!  "WENIG" is not a good choice because it doesn't use all the letters.   So "WENIGES" is the best choice and it is indeed the correct answer.